COLONIZATION OF DENTAL PLAQUE - A SOURCE OF NOSOCOMIAL INFECTIONS IN INTENSIVE-CARE UNIT PATIENTS

Objective: To study the dental status and colonization of dental plaqu e by aerobic pathogens and their relation with nosocomial infections i n intensive care unit (ICU) patients. Design: A prospective study in a medical ICU of a university-affiliated hospital. Patients: Consecutiv e patients admitted to the ICU during a 3-mo period. Interventions: De ntal status was assessed by the same investigator using a score adapte d from the ''Caries-Absent-Occluded'' (CAO) index (referred to in the U.S. as DMFT [Decayed-Missing-Filled Teeth] index), The amount of dent al plaque on premolars was assessed using a semiquantitative score, Qu antitative cultures of dental plaque, nasal secretions, tracheal aspir ates, and urine were done at admission (day 0) and every fifth day unt il death or discharge. An additional study was done in eight patients to serially compare dental plaque, salivary, and tracheal aspirate cul tures during a 2-wk period. Meaurements and Main Results: Fifty-seven patients were included in the main study. Due to the variability in th eir ICU stay, 29 patients could be examined on day 0 only (group A), 1 5 patients on days 0 and 5 (group B), and 13 patients on days 0, 5, an d 10 (group C), The mean dental CAO score was 16 +/- 8 and did not cha nge during the ICU stay, The dental plaque score was less than or equa l to 1 in 70% of patients on day 0; greater than or equal to 2 in 50% of patients on day 5; and greater than or equal to in 90% of patients on day 10, Dental plaque cultures were positive at 10(3) colony-formin g units/mL for aerobic pathogens in 23% of patients on day 0; 39% of p atients on day 5; and 46% of patients on day 10. in groups B and C, me an dental plaque score and frequency of plaque colonization increased from days 0 to 5 and from days 5 to 10. A high bacterial concordance w as found between dental plaque and tracheal aspirate cultures, and in the additional study, between salivary and dental plaque cultures, Twe nty-one patients developed a nosocomial infection in the ICU. Dental p laque colonization on days 0 and 5 was significantly associated with t he occurrence of nosocomial pneumonia and bacteremia (sensitivity 0.77 ; specificity 0.96; positive predictive value 0.87; negative predictiv e value 0.91; relative risk 9.6), In six cases of nosocomial infection , the pathogen isolated from dental plaque was the first identified so urce of nosocomial infection, Conclusions: The amount of dental plaque increased during the ICU stay. Colonization of dental plaque was eith er present on admission or acquired in 40% of patients,A positive dent al plaque culture was significantly associated with subsequent nosocom ial infections, Dental plaque colonization by aerobic pathogens might be a specific source of nosocomial infection in ICU patients.